Seeking Temporary Roof Repair Advice

[Airhead59]

I've developed a roof leak and looking for advice on a temporary, on-the-road repair. Can I put a silicone or other hardware store caulking over a crack in the existing caulking (Dicor? Sikaflex?) around the Fantastic Fan?

Background: I've read lots of forum threads over the last couple of years about what a PIA it is to strip and replace roof caulking around penetrations. Consequently, I put it off too long. I'm traveling until late July and I just want to limit the amount of water intrusion/damage until I get home and can do the job right. Are there caulking materials that will adhere to the existing, aged and failing material? How should I clean/prepare the surface for maximum chance of success?

[Boxite]

Sikaflex 715 has worked perfectly for that very purpose for us. Sealed it up, it self levelled…it’s still flexible and does the job.
Sika 221 takes up to 5 days to cure….715 cures in hours and lasts for years if not forever because it stays flexible.
Dicor will eventually dry out and crack.

Follow the directions on the tube. I didn’t even remove the old cracked whatever Airstream put up there… I just pumped Sika 715 on top of it…. it levelled out…and looks like it’s the only thing up there, completely covering and sealing up over the old stuff, 7+ years now.

[ROBERT CROSS]

Originally Posted by Airhead59

I've developed a roof leak and looking for advice on a temporary, on-the-road repair. Can I put a silicone or other hardware store caulking over a crack in the existing caulking (Dicor? Sikaflex?) around the Fantastic Fan?

Background: I've read lots of forum threads over the last couple of years about what a PIA it is to strip and replace roof caulking around penetrations. Consequently, I put it off too long. I'm traveling until late July and I just want to limit the amount of water intrusion/damage until I get home and can do the job right. Are there caulking materials that will adhere to the existing, aged and failing material? How should I clean/prepare the surface for maximum chance of success?

I used this for all our leaking vents & skylights as a 'temporary' emergency fix eight years ago, (before it got popular & Expensive.

Luckily I've still got some for another emergency.

One of Gorilla's offerings may be a suitable substitute.

Bob
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[Airhead59]

Thanks for your responses. I will give it a try with Sikaflex 715.

[richard5933]

If there is currently Dicor, it should peel back with a putty knife enough to expose clean material. Or, use mineral spirits on a rag to clean the surface.

After either of those, apply more Dicor self leveling. Best not to mix caulking, even for short term. Also need a clean surface or the new stuff won't adhere. Any RV place will have Dicor or you can order from Amazon for next day delivery.

[Airhead59]

How can I tell which sealer was used previously, Sikaflex or Dicor?

[ROBERT CROSS]

Originally Posted by Airhead59

How can I tell which sealer was used previously, Sikaflex or Dicor?

Are we now talking about a 'permanent' fix?

I can't help with Sika or Dicor... 3M 5200 or 4200 fast cure

Happy Sealing...

Bob
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[richard5933]

Originally Posted by Airhead59

How can I tell which sealer was used previously, Sikaflex or Dicor?

Dicor self-leveling will have a very smooth appearance and look like it flowed out in all directions as it self leveled. It has a very characteristic look & feel. Here's a photo of what Dicor looks like after it's self-leveled.

I believe that the Sikaflex will look more like traditional caulking, although they might have a self-leveling version as well.

[DaveP]

If you use the 3M 4412N tape Bob is suggesting, it is super sticky and require no curing time (and it can be the permanent solution). It can be rained on right after installation. I have used on seams around the skylight with great success without digging out the old caulk. Just remove any loose caulk and give the surface a quick cleaning with alcohol or another solvent. Amazon keeps it in stock for 1 day delivery where I live.

[ROBERT CROSS]

Originally Posted by DaveP

If you use the 3M 4412N tape Bob is suggesting, it is super sticky and require no curing time (and it can be the permanent solution). It can be rained on right after installation. I have used on seams around the skylight with great success without digging out the old caulk. Just remove any loose caulk and give the surface a quick cleaning with alcohol or another solvent. Amazon keeps it in stock for 1 day delivery where I live.

I bought several 3" wide rolls 6yrs ago at $38ea they are now over $83.

Bob
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[DonRich7878]

I see a temporary patch as a short term repair performed while in route on the side of the road. This type of repair can effectively be performed with bubble gum, duck tape, trash bags and baling wire. Once you are securely landed and parked, follow Bob’s recommendation…

[Airhead59]

After reading the recommendations and comments from the Forum, I completed what I hope is not a temporary, but long-term repair of the seal around my Fantastic Fan. I ordered a tube of SikaFlex 715 from Amazon, removed as much of the existing, cracked caulk, cleaned with acetone and re-sealed the fan housing penertation. When I get home I'll need to take stock of the other roof penetratioms and repair those as necessary. Before, during and after photos attached.

Thanks to the forum members above for advice and encouragement to tackle this job.

[ROBERT CROSS]

Same job we did years ago with 3M 4412N.

Bob
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[jcanavera]

My dealer did a strip and seal job on my roof in January. Also replaced two cracked skylights too. Not cheap. About 10-11 hours to do it right. Skylight replacement was another $400. Didn't want to spend that much but after almost 20 years (thankfully inside storage for 18 years) allowed me to get by that long. My age however has gotten to me and I just don't have the ability to deal with heights any more. I'd rather spend the $$ than fall off the roof. We had him booked for the skylights but once they got up there and looked at the caulking around all the roof penetrations, he said he was surprised that the only leaks I had were from those cracks in each skylight. Thankfully the leaks didn't show till my last trip of the year and they came straight down from the skylight frames into the shaft. Just some small drips.

Jack

[richard5933]

Looks like this should solve your leak problems. Only thought I have is about the use of a non-self leveling caulking for something like this as it makes it more difficult to keep clean in the future. When I clean off the roof between trips to remove leaves and debris, the Dicor self-leveling never seems to hold as much crud as the places I've used Sikaflex or another non-self leveling caulk.

Lots of people seem to like the Sikaflex products over Dicor - do they make a self-leveling caulk? Or any other company which has a self-leveling product better than the Dicor. I've never had a problem with the Dicor, but am certainly open to better caulking if it's out there.

[Airhead59]

SikaFlex 715 is labeled "semi-self leveling". The photos I took were immediately after application. I'm planning to take a look today and see if it leveled itself any more.

[Vlamgat]

Following

[Mark of SJC]

We had a similar issue in the middle of a rainy Oregon trip. Worse yet, we couldn't quite figure out where the leak was coming from (more on that in a second).

I didn't have a ladder and didn't want to try and get on the roof. I went to Home Depot and bought a long roll of plastic tarp (think carpet runner). and literally threw it over the top of the coach where the leak was presenting on the inside. It was lightweight enough to "mold/stick" to the coach exterior, yet had enough weight to be "thrown" easily...and repeatedly, as we used it for over a week, changing camp grounds several times. Obviously, not a permanent solution, but it really worked great!

As for the source - it was our forward skylight...whose plastic structure had less strength than a clear plastic salad container! We discovered a far superior (and surprisingly not-that-expensive) alternative in Maxium skylights. Did the replacement myself (90% from the INSIDE of the coach, and never had to get on the roof!). 1,000% recommend https://maximskylights.com/airstream-skylights/